U.S. patent application number 10/568872 was filed with the patent office on 2007-08-23 for mounting for disk drive unit, retaining device and method of loading a disk drive unit.
This patent application is currently assigned to XYRATEX TECHNOLOGY LIMITED. Invention is credited to Andrew William Atkins.
Application Number | 20070195497 10/568872 |
Document ID | / |
Family ID | 34272987 |
Filed Date | 2007-08-23 |
United States Patent
Application |
20070195497 |
Kind Code |
A1 |
Atkins; Andrew William |
August 23, 2007 |
Mounting for disk drive unit, retaining device and method of
loading a disk drive unit
Abstract
A mounting for a disk drive unit includes a carrier for carrying
a disk drive unit during required movement of the disk drive unit.
The carrier defines a space into which the disk drive unit can be
inserted, and the carrier is adapted to be inserted with the disk
drive unit into a receiving frame for operational use. At lease two
resilient devices are mounted on the carrier for securing the disk
drive unit in the receiving frame when the carrier is inserted into
the frame, at least one resilient device being mounted on each side
of the carrier. Each resilient device is movably mounted on the
carrier to allow movement of the device as a whole relative to the
carrier, and the resilient device is arranged to secure the disk
drive unit in the receiving frame by acting between disk drive unit
and the receiving frame. A method of handling the disk drive unit
comprises placing the disk drive unit into the carrier engaging a
robotic device with a coupling structure projecting from the front
of the carrier. The method then includes lifting the carrier by the
robotic device and inserting the carrier into a receiving frame by
a substantially horizontal movement.
Inventors: |
Atkins; Andrew William;
(Southampton, GB) |
Correspondence
Address: |
PILLSBURY WINTHROP SHAW PITTMAN, LLP
P.O. BOX 10500
MCLEAN
VA
22102
US
|
Assignee: |
XYRATEX TECHNOLOGY LIMITED
Langstone Road, Havant
Hampshire
GB
P09 ISA
|
Family ID: |
34272987 |
Appl. No.: |
10/568872 |
Filed: |
September 7, 2004 |
PCT Filed: |
September 7, 2004 |
PCT NO: |
PCT/GB04/03812 |
371 Date: |
July 28, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60500693 |
Sep 8, 2003 |
|
|
|
Current U.S.
Class: |
361/679.33 ;
G9B/33.026 |
Current CPC
Class: |
G11B 33/12 20130101;
G11B 33/08 20130101 |
Class at
Publication: |
361/685 |
International
Class: |
G06F 1/16 20060101
G06F001/16 |
Claims
1. A mounting for a disk drive unit, the mounting comprising: a
carrier for carrying a disk drive unit during required movement of
a said disk drive unit, the carrier defining a space into which a
said disk drive unit can be inserted; and, at least one retaining
device mounted on the carrier for securing a said disk drive unit
in the carrier, in which the or each retaining device is pivotally
mounted on the carrier and is arranged to provide vertical
positioning control of a said disk drive unit in the carrier.
2. A mounting according to claim 1, in which the retaining device
comprises an engaging member to engage with a corresponding
engaging member on a disk drive unit when a disk drive unit is
arranged within the carrier.
3. A mounting according to claim 2, in which the engaging member on
the retaining device comprises a projection adapted to be received
in a corresponding recess in a said disk drive unit.
4. A mounting according to any of claim 2, wherein the at least one
retaining device is pivotally connected to the carrier in such a
manner that in a rest position the engaging member is biased into
the carrier.
5. A mounting according to claim 2, in which the or each retaining
device comprises a spring member to bias the engaging member into
the carrier.
6. A mounting according to claim 2, in which the carrier is adapted
to be inserted with a disk drive unit into a receiving frame for
operational use and the at least one retaining device comprises a
first end at which the engaging member is arranged and a second
distal end, a pivot being provided between the first and second
end, wherein at the first end on an external face of the retaining
device a damper is provided.
7. A mounting according to claim 8, in which the damper comprises a
damping material selected from the group consisting of sorbathane
and silicone-free gel.
8. A mounting according to claim 1, in which shock mounts are
provided on a base of the carrier to receive a disk drive unit.
9. A mounting according to claim 8, in which the shock mounts
comprise spigots arranged on a base of shock absorbing
material.
10. A mounting according to claim 1, comprising a disk drive unit
therein.
11. A mounting according to claim 1, wherein the axis of rotation
of the pivotally mounted retaining device is substantially
perpendicular to the plane of the bottom of the space into which a
said disk drive unit is inserted.
12. A mounting according to claim 1, in which there are provided
four retaining devices.
13. A retaining device for retaining a disk drive unit in a
mounting device according to claim 1, the retaining device
comprising: a connection point for pivotal connection to the
mounting device and a spring member to bias the retaining device
into the carrier of the mounting device when in rest position.
14. A retaining device according to claim 13, comprising a first
end having an engagement member and a distal end, the connection
point being provided between the first end and distal end.
15. A retaining device according to claim 14, comprising a damper
provided on an external face of the first end.
16. A method of loading a disk drive unit into a mounting having a
carrier for a disk drive unit and comprising at least one retaining
device mounted on the carrier for securing a said disk drive unit
in the carrier, in which the or each retaining device is pivotally
mounted on the carrier and is provided with an engaging member to
engage a said disk drive and arranged to provide vertical
positioning control of a said disk drive unit in the carrier, the
method comprising: inserting a said disk drive unit into the
carrier such that the or each retaining member acts on a said disk
drive unit to maintain a said disk drive unit in the carrier.
17. A method according to claim 16, comprising: acting on the or
each retaining member in such a manner to cause the or each
engaging member to move out of the carrier; inserting a said disk
drive unit into the carrier when the or each retaining member is in
this outer position; and, releasing the or each retaining member to
grip a said disk drive unit in position in the carrier.
18. A method of loading a disk drive unit into a mounting having a
carrier for a disk drive unit and comprising at least one retaining
device having an engaging member and being pivotally inserted at
the carrier for engaging interaction with a disk drive unit, the
method comprising: pivoting said at least one retainer device about
its pivotal mount in a first direction such that the engaging
member is located outside said carrier; inserting a disk drive unit
into the carrier; pivoting said at least one retaining device about
its pivotal mount in a second direction such that the engaging
member engages said disk drive unit.
Description
[0001] The present invention relates in one aspect to a mounting
for a disk drive unit such as disk drive unit which has a data
storage disk, a movable disk head and main body supporting the disk
and the head. The present invention relates in another aspect to a
retaining device and a method of loading a disk drive unit into a
mounting.
[0002] In a conventional disk drive unit the data storage disk is
usually mounted horizontally for rotation about a vertical axis,
and is mounted in a main chassis body. The disk head, which may be
a read only head or a read and write head, is movably mounted on
the main body of the disk drive unit, for movement over the disk to
desired tracks. Although in some circumstances the disk drive unit
may be permanently and rigidly fixed in a frame of other equipment,
it often occurs that the disk drive unit must be mounted so as to
be easily removable from a supporting frame. For example in a
tester rack it is conventional to fit each disk drive unit into a
separate carrier moulded of plastics material, and for the carrier
then to be slotted into the tester rack. In other applications, a
removable disk drive unit may be removably mounted in a
computer.
[0003] In some arrangements the disk drive unit may be mounted
vertically for rotation about a horizontal axis. In general in this
specification, where an example of a disk drive unit is described
with the disk in a horizontal plane, it is to be appreciated that
the description applies equally well to a disk drive unit
positioned in a vertical plane for rotation about a horizontal
axis, or indeed in other configurations where appropriate.
[0004] A problem which arises in the operation of disk drive units
occurs at the end of the seek movement of the disk head to a
desired track. The access acceleration and deceleration of the
actuator, containing the read/write heads, particularly on high
performance disk drive units, results in an equivalent reaction to
the main body of the disk drive unit. This reaction can cause the
disk drive unit to oscillate in its mounting, and hence the
reaction provides an input to the disk drive unit. The result is
unwanted misregistration of the head to the track. In recent years
the actuators on disk drive units have generally changed from
linear to rotary operation, the read/write heads being moved in an
arc across the disk, about a vertical axis (for a horizontal disk)
positioned on the main body of the disk drive unit, outside the
perimeter of the disk. The vibrations arising from acceleration and
deceleration of such a rotary actuator produce rotary oscillation
of the main body of the disk drive unit in a horizontal plane.
[0005] One way of reducing or avoiding the effects of such
vibration is to mount the main body of the disk drive unit very
firmly in a grounded frame, secured against rotary vibration, and
another method is to mount the main body of the disk drive unit on
a floating mounting, or one which allows movement only at such a
low frequency that the actuator servo can follow the vibration with
only a small error. If the disk drive unit is not mounted at one of
these extremes (rigidly mounted or on a floating mounting) the
mount vibration will appear on the head/track error signal after
the disk drive unit has met its on-track criteria. The resulting
misregistration is detected, causing what is generally known as a
Write Fault Error, preventing the disk drive unit from writing,
with a consequent reduction in performance of the disk drive
unit.
[0006] In situations where easy removability of the disk drive unit
is required, mounting at either of the extreme situations mentioned
above is difficult. In a disk drive unit tester rack for example,
removal should be as simple as possible. Nowadays, there is a
desire for automation of movement of disk drive units and
associated mountings such that there is an increased need for a
mounting of a disk drive unit that is robust and enables easy
automatic handling to be achieved.
[0007] In WO-A-01141148 there is disclosed apparatus for testing
disk drive units including a supporting structure for supporting a
disk drive unit, referred to in the disclosure as a disk drive unit
carrier, adapted to carry a disk drive unit and a temperature
control device for controlling the temperature of the disk drive
unit to be at a predetermined temperature during operation of the
disk drive unit. An air flow control device controls the flow of
air across the disk drive unit. In some arrangements there may be
provided disk drive unit test apparatus for receiving a plurality
of disk drive units, the test apparatus comprising a plurality of
carriers each for receiving a respective disk drive unit. In the
example described in this specification, the apparatus has a door
at the front which can be opened or removed to allow a disk drive
unit to be inserted into or removed from the carrier. A plurality
of such carriers can be incorporated in or assembled into disk
drive unit test apparatus, such as for example a test rack. This
allows individual disk drive units to be moved into and out of the
test apparatus.
[0008] It has been known in the past to secure a disk drive unit
rigidly in a carrier by use of wedges. In WO-A-97106532 a mounting
for a disk drive unit comprises a supporting structure for
supporting a disk drive unit, referred to in the disclosure as a
carrier, defining a space into which the disk drive unit can be
removably inserted for operational use. The carrier has a base and
two opposed sides, and first and second wedge means which are
movable to act between the main body of the disk drive unit and the
side of the carrier, to secure the disk drive unit against movement
relative to the carrier. The wedge means include wedges which are
movable in a vertical direction by a control linkage operated
automatically when the disk drive unit is inserted into the
carrier. A disadvantage of the rigid mounting disclosed in
WO-A-97/06532 is that where a plurality of disk drive units are
mounted together in a common frame, for example in a tester, the
rigid mounting results in cross torque between adjacent disk drive
units during testing. Thus the rigid mounting allows transmission
of high frequency disturbances from one disk drive unit to another.
Thus although the rigid mounting can cure errors arising from the
inertia of the disk head during movement, it can result in a
further difficulty in cross talk (i.e. the transmission of
vibration between adjacent drives) between disk drive units.
[0009] In U.S. Pat. No. 6,209,842 (Anderson et al) there is
disclosed a mounting for a disk drive unit comprising a carrier for
carrying the disk drive unit and four resilient members referred to
as damping devices mounted on the carrier for securing the disk
drive unit in a receiving frame, referred to as a system cabinet.
The resilient elements are positioned two on each side of the
carrier, two positioned towards the front of the carrier and two
positioned towards the rear of the carrier. In operation the disk
drive unit is mounted in the carrier which in turn is pushed into a
bay defined by side walls of the bay. The damping devices are
mounted on the carrier by bolts.
[0010] In WO-A-03/021597 there is disclosed a mounting for a disk
drive unit. At least one retaining device is provided in such a
manner that it is movably mounted on a carrier to allow movement of
the retaining device as a whole.
[0011] According to a first aspect of the present invention there
is provided a mounting for a disk drive unit, the mounting
comprising: a carrier for carrying a disk drive unit during
required movement of a said disk drive unit, the carrier defining a
space into which a said disk drive unit can be inserted; and, at
least one retaining device mounted on the carrier for securing a
said disk drive unit in the carrier, in which the or each retaining
device is pivotally mounted on the carrier and is arranged to
provide vertical positioning control of a said disk drive unit in
the carrier.
[0012] The invention provides a mounting for a disk drive unit, the
mounting including a carrier and at least one retaining device
mounted on the carrier. The retaining device is pivotally mounted
on the carrier and is arranged to provide vertical positioning
control of a disk drive unit in the carrier. The invention provides
a mounting that enables robust and simple automatic handling of a
mounting to be achieved. In particular, since vertical positioning
control of the disk drive is provided by the pivotally mounted
retaining device, a mounting having a disk drive unit therein can
even be turned upside down without the disk drive unit falling out.
This is clearly advantageous. Furthermore the mounting of the
present invention enables easy insertion and removal of a disk
drive unit to or from the mounting to be achieved.
[0013] According to a second aspect of the present invention, there
is provided a retaining device for retaining a disk drive unit in a
mounting device according to any preceding claim, the retaining
device comprising: a connection point for pivotal connection to the
mounting device and a spring member to bias the retaining device
into the carrier of the mounting device when in rest position.
[0014] According to a third aspect of the present invention, there
is provided a method of loading a disk drive unit into a mounting
having a carrier for a disk drive unit and comprising at least one
retaining device mounted on the carrier for securing a said disk
drive unit in the carrier, in which the or each retaining device is
pivotally mounted on the carrier and is provided with an engaging
member to engage a said disk drive and arranged to provide vertical
positioning control of a said disk drive unit in the carrier, the
method comprising: inserting a said disk drive unit into the
carrier such that the or each retaining member acts on a said disk
drive unit to maintain a said disk drive unit in the carrier.
[0015] It is to be appreciated that where features of the invention
are set out herein with regard to apparatus according to the
invention, such features may also be provided with regard to a
method according to the invention, and vice versa.
[0016] Embodiments of the invention will now be described by way of
example with reference to the accompanying drawings in which:--
[0017] FIG. 1 is a diagrammatic perspective view from above of an
example of a mounting for a disk drive unit embodying the
invention;
[0018] FIG. 2 is perspective view of a retaining device for
retaining a disk drive unit in the mounting shown in FIG. 1;
[0019] FIG. 3 is a plan view from above of the retaining device of
FIG. 2;
[0020] FIG. 4 shows a schematic cross section of a retaining device
in position in a carrier wall;
[0021] FIG. 5 shows a schematic cross section of a retaining device
in position in a carrier wall; and,
[0022] FIG. 6 is a diagrammatic perspective view shown partly from
above, of a tester rack for receiving a plurality of disk drive
units.
[0023] FIG. 1 shows a mounting 2 embodying the invention, for a
disk drive unit 1 shown schematically in phantom. The mounting 2
comprises a carrier 4, also referred to as a carrier tray, for
carrying a disk drive unit during required movement of the disk
drive unit. The carrier 4 defines a space into which the disk drive
unit can be inserted. The carrier 4 is adapted to be inserted with
the disk drive unit into a receiving frame 30 shown by way of
example in FIG. 5 as a tester rack 32. The receiving frame 30 of
FIG. 5 provides a plurality of bays 34 each having a supporting
structure including a pair of side rails 36, to be described more
fully hereinafter. Referring again to FIG. 1, the carrier 4 is
formed by two side wall portions 6, a front wall 8, a rear wall 10
and a floor 12. A retaining assembly for retaining the disk drive
unit in the carrier includes four retaining devices 14 positioned
with two retaining devices 14 towards the front of the carrier 4,
and two retaining devices towards the rear of the carrier 4. Guide
rails 13 are provided on the side walls 6 of the carrier 4. Holes 7
are provided at the rear end of the carrier 4, for engagement with
e.g. a temperature control device, such as that described in our
copending international application (agent's ref. AF2/P9715WO) of
even date herewith.
[0024] As shown in FIG. 2, in this embodiment, each retaining
device 14 comprises a first end 16 and a distal end 18. Each
retaining device 14 also comprises an engaging member 20 (FIG. 3)
arranged generally at the first end 16, the engaging member being
operative to engage a disk drive unit when provided in the carrier
4. Each retaining device 14 is adapted to be pivotally mounted on
the carrier 4. The distal end 18 of each retaining device 14
comprises a spring member and when in position in a carrier 4, the
spring member 18 is operative to bias the first end 16 and the
corresponding engaging member 20 into the carrier 4.
[0025] Considering now the construction of the retaining device 14
in detail, reference will be made to FIGS. 2 and 3. As shown in
FIG. 2, each retaining device 14 comprises a first end 16 and a
distal end 18. A pivot 22 is provided which enables rotation of the
retaining device 14 about axis 24 shown in FIG. 2. The distal end
18 is formed from a resilient material so that it can function as a
biasing spring when the retaining device 14 is arranged in a
carrier 4. A lip 26 is provided at the first end 16 of the
retaining device 14, and serves to limit movement of the retaining
device, as will be explained in more detail later.
[0026] FIG. 4 shows a schematic cross section of a retaining device
14 in position in a carrier wall 6. It can be seen that in this
rest position i.e. a position in which the retaining device 14 is
arranged in carrier 4 but no disk drive unit is provided in carrier
4, engaging member 20 is arranged inside the carrier
(left-hand-side of wall 6 in FIG. 3). The lip 26 provided at the
first end 16 of the retaining device 14 functions to limit the
distance into the carrier 4 that the engaging member 20 can travel
through opening 28 in wall 6. This is achieved by engagement of the
lip 26 with the side wall. For reasons of clarity, a spacing is
shown between the lip 26 and wall 6, however it will be appreciated
that in position in the carrier 4, the lip 26 is usually but not
always engaged with the wall 6.
[0027] Referring to all of FIGS. 3 and 4, a curved member 30 is
provided on the outer (outer with respect to the space in carrier
4) side of retaining device 14. This member 30 defines a region 32
between the body of the retaining device 14 and the member 30. As
will be explained below, this region 32 can be filled with a
selected material to provide damping for a disk drive unit arranged
within the carrier 4.
[0028] In a rest position the engaging member 20 of each retaining
device 14 projects into the carrier 4 and is biased into this
position by means of the spring 18. As explained above, the amount
it projects into the carrier 4 is limited by interaction between
the lip 26 and the wall 6.
[0029] When a disk drive unit is inserted into the carrier 4, the
retaining device 14 is caused to pivot about its pivotal axis 24
against the bias of the spring 18 which thereby imparts a
restraining force onto the disk drive unit being positioned within
the carrier 4. The bias provided by the springs 18 and the
retaining devices 14 is sufficient to maintain the disk drive unit
in the carrier so that if, for example, jogged or knocked or even
turned up-side-down in operation, the disk drive unit will be
maintained within the carrier 4. As mentioned above, this is
important in instances where disk drive units are moved
automatically into and out of tester racks. It will be appreciated
that the retaining device 14 can be provided as an independent unit
for putting into a carrier 4 or alternatively it can be provided as
an integral part of the carrier 4.
[0030] There will now be described with reference to FIGS. 1 and 6,
the way in which a disk drive unit is inserted into a carrier 4.
This may be done manually or alternatively automatically, for
example, with the use of a robot. A disk drive unit can simply be
positioned within the carrier 4 such that on entry into the carrier
4 the engaging members 20 of the restraining devices 14 are forced
outwards by the contact with a side wall of the disk drive
unit.
[0031] As will be explained below in an alternative method, it is
possible to configure the retaining devices temporarily so that the
engaging members 20 are positioned outside of the carrier 4. This
is achieved by applying a force against the resilient member 18
between the pivot 22 in a region where a spacing is allowed in the
wall of the carrier 4 to allow movement of the spring 18.
[0032] FIG. 5 shows a retaining device 14 in such a position. A
force is applied in a direction of the interior of the carrier 4
and this causes a clockwise rotation of the first end 16 of the
retaining device 14 about its pivot 22. With the retaining device
in this configuration, a disk drive unit can be inserted into the
carrier without any contact with the engaging member 20. In this
position, the engaging member is arranged outside the space within
the carrier. Accordingly, when a disk drive unit is then inserted
into the carrier 4, there is initially no direct interaction with
the retaining device 14. Once the force applied is removed, the
retaining device 14 under the bias of spring 18 engages the disk
drive unit. This is advantageous if there is a risk of damage of
the disk drive unit by virtue of the interaction between the disk
drive unit and the engaging member 20 of the retaining devices 14.
The operation described above can be performed automatically by
suitably arranged apparatus having an appropriately designed
projection or finger automatically or manually to provide the force
required to ensure the engaging member 20 is temporarily outside
the carrier 4.
[0033] When a disk drive is inserted into the carrier 4, it is
retained within the carrier by the action of the retaining devices
14. There will now be described with reference to FIGS. 1 and 6,
the operation of the retaining devices 14 clamping a disk drive
unit into the carrier 4 when, for example, the carrier and disk
drive unit are inserted into a tester rack.
[0034] FIG. 6 is a diagrammatic perspective view shown partly from
above, of a tester rack for receiving a plurality of disk drive
units. In FIG. 6, there is shown a tester rack for housing disk
drive units for testing. The rack provides a plurality of bays each
having side rails 44 which locate in the guide rails 13 provided on
the side walls 6 of the carrier 4. Each side rail 44 extends
inwardly of the guide rails 13 on the carrier 4. The effect of this
is that when the carrier 4 is fully installed and engaged with the
side rails 44 the retaining devices 14 are engaged by the side
rails 44 such that member 30 of each retaining device 14 is forced
towards the body of the retaining devices 14 to which it is
connected.
[0035] This has the effect of increasing the clamping force on the
disk drive unit in the carrier 4. Of course, since lip 26 of the
retaining device 14 will already be engaged with the side wall 6 of
the carrier 4 (explained above), there will be no further inwards
movement of the engaging member 20. However, the force with which
the engaging member is maintained in contact with the disk drive
unit is increased.
[0036] The engagement between the side rails 44 of the tester rack
and the retaining members 14 is via the curved members 30. As
explained above, each curved member 30 is resilient and the opening
side of 32 is therefore reduced as a result of contact between the
guide rails 44 and the retaining device 14. In a preferred example
of the present invention, a damping material is provided within the
opening 32. This ensures that when a disk drive is arranged within
a carrier in the tester rack, vibration of the disk drive under
test is damped. Suitable materials that may be used to provide
damping include visco-elastic polymers such as visco-elastic
polymers manufactured by Sorbothane, Inc., silicone-free damping
gel, or any other material capable of providing suitable damping.
It will be appreciated that in some cases no material may be added
to the opening 32 and that in such cases, sufficient damping is
provided by the retaining device 14 itself.
[0037] The mounting described above can be used for mounting a disk
drive unit for insertion into a test rack. The mounting can also be
used as a mounting for a disk drive unit during normal operation of
the disk drive unit by an end user.
[0038] It will be understood that each engaging member 20 provided
on the first end 16 of each retaining device 14, engages with a
corresponding hole or depression in the side of a disk drive unit
in place in the carrier. Disk drive units typically (according to
accepted international standards) are provided with positioning
holes to enable the disk drive to be positioned and locked in place
e.g. in a computer. The retaining devices 14 are preferably
arranged in the carrier 4, such that their corresponding engaging
members 20 will present at the points where the holes or
depressions are provided in the disk drive units according to the
accepted standards. It will also be appreciated that the engaging
member 20 provided on the retaining device 14 may be a hole or a
depression to engage with a corresponding projection, if such
exists, on the body of a disk drive unit.
[0039] In one example of the present invention, there are provided
on the floor 12 of the carrier 4 a number of shock mounts 15. The
shock mounts 15 serve to locate and support a disk drive unit when
loaded in the carrier 4. The shock mounts 15 may be provided with
spigots or any other means by which the disk drive unit can be
located. The shock mounts are typically made of a material which is
suitable to provide sufficient shock absorbency. Examples of
suitable materials include visco-elastic polymers or any other
material capable of providing sufficient shock absorbency. The
shock mounts or spigots provide alignment of a disk drive unit
inserted into the carrier either before or during engagement of the
retaining devices 14. Furthermore, the spigots, which will engage
with corresponding features on the underside of an inserted disk
drive unit, provide restraint of the disk drive unit in a lateral
direction during electrical connection to the disk drive unit. The
electrical connection could be plugging or unplugging of a disk
drive unit inserted in a tester rack as discussed above.
[0040] In addition, one or more air vents 17 may be provided on the
bottom of the carrier 4 to enable a flow of air within the carrier.
This flow of air can be used to regulate the temperature of the
disk drive unit within the carrier 4. Reference is made to our
copending International application (agents ref. AF2/P9715WO) of
even date herewith, the entire content of which is hereby
incorporated by reference.
[0041] There will now be described, with reference to FIG. 5, the
overall operation of a carrier 4, loaded with a disk drive unit,
into a tester rack. After the disk drive unit has been placed in
the carrier 4, the carrier 4 is then presented to the tester rack
42, and engaged with the rails 44 as has been described above. The
carrier 4 is then pushed home into the rack 42, and the retaining
devices 14 are further engaged by the rails 44, so that the disk
drive unit is firmly clamped by the retaining devices 14 being
compressed.
[0042] During insertion of the carrier 4 into the rack 42,
electrical connection is made between electrical connectors (not
shown) on the inner, rear end of the disk drive unit and
corresponding electrical connectors provided in the inner end
region of each bay 43. In prior art arrangements where a disk drive
unit has been rigidly clamped in a tester rack (for example as
discussed above with reference to WO 97/06532) it has been
necessary to provide that the electrical connector in the rear of
the bay 43 has a floating mounting, to allow the connector to mate
with the other connector when the disk drive unit is rigidly
clamped. However in the embodiment shown in the Figures is not
necessary. The electrical connector on the tester rack, and the
electrical connector on the disk drive unit, may each be rigidly
mounted. A suitable tapered lead-in is provided at each connector,
so that any slight misalignment due to tolerance, is taken up by
movement of the entire disk drive unit relative to the carrier 4.
Because the retaining devices 14 allow a small amount of movement,
whilst retaining the required clamping characteristics, the
tolerances can be taken up by movement of the entire disk drive
unit, rather than by movement of electrical connectors in a
floating mounting relative to the tester rack. This allows
simplification in the manufacture of the tester rack, with
consequent savings in manufacturing costs, and maintenance
costs.
[0043] In the embodiment described with reference to the drawings,
a number of features combine to give an advantageous arrangement.
The action of sliding the carrier 4 into the receiving frame causes
the retaining devices 14 to be compressed by means of the rails 44,
which have a taper at the leading edge to facilitate a progressive
clamping action. The single action of installing the carrier tray
containing the disk drive unit into the receiving frame enables the
electrical connector (not shown) at the rear of the disk drive unit
to align and connect with the corresponding connector in the
receiving frame. The provision of lateral movement of the disk
drive unit against the retaining devices provides that
manufacturing tolerances can be allowed for without the need for a
floating electrical connector at the rear of the receiving bay. The
amount of lateral movement of the disk drive unit is within the
limit of the movement enabled by the damping provided by the
retaining devices as described above.
[0044] The overall arrangement illustrated has a low space
requirement. The carrier tray with the retaining devices includes
all of the clamping mechanism so that it is not necessary to
suspend operation of an overall test system to service the clamping
mechanism. The clamping mechanism can be serviced individually for
each carrier.
[0045] It is to be appreciated that although in the embodiments
illustrated and described hereinbefore there are shown four
retaining devices 14 positioned approximately one at each corner of
the carrier 4, numerous other arrangements can be provided in
accordance with the invention. For example although it is preferred
that at least one retaining device 14 is provided on each side of
the carrier 4, at least some of the advantages of the invention can
be obtained by providing a single retaining device 14 on one side
of the carrier 4, with one or more fixed locations on the other
side of the carrier 4 projecting from the side walls of the carrier
4 and locating against the side of the disk drive unit.
[0046] Numerous other arrangements can be made, for example two
retaining devices 14 on one side of the carrier, and a single
retaining device 14 on the other side of the carrier; two floating
retaining devices 14 on one side of the carrier 4, and a single
fixed location contact on the other side projecting from the
carrier 4 to contact with the side of the disk drive; or two
retaining devices 14, positioned one on each side of the carrier
4.
[0047] Embodiments of the present invention has been described with
particular reference to the examples illustrated. However, it will
be appreciated that variations and modifications may be made to the
example described within the scope of the present invention.
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